Carburetor



Nov. 6, 1923. 1,472,834

R. s. HILL CARBURETOR Filed Jan. 23 1919 2 Sheets-Sheet l %n/m/m 42/4 7 wad we atented Nov. 6, 1923.

' BAYMOND'S. HILL, OF MINNEAPOLIS, MINNESOTA.

CARBUBETOR.

Application filed January To all whom it may concern:

Be it known that I, RAYMOND S. HILL, a citizen of the United States residing at Minneapolis, in the county of Iiennepin and State of Minnesota, have invented certain new and useful Improvements in Carburetore; and I do hereby declare the following to be a full, clear, and exact-description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to carburetors for internal combustion engines, and has for its object to simplify the construction and improve the operation thereof. This carburetor is of a type wherein the air 1s preheated, in part, before it is delivered to the manifold. The hydrocarbon liquid is taken up bythe air that is to be preheated and the initial vaporization is insured by the heat afforded by the exhaust from the engine.

A carburetor involving the above noted features, and others, is illustrated in the accompan ing drawings, wherein like'characters in icate like parts throughout the several views.

Referring'to the drawings,

Fig. 1 is a side elevation showing the carburetor applied to a multicylinder internal combustion engine;

Fig. 2 shows the carburetor partly in section on the line 2-2 and partly in section on the line 2- a of Fig. 3; and

Fig. 3 is a fragmentary horizontal section on the line 3-3 of Fig. 2, and Fig. 4. is a fragmental horizontal sectional on the line H of Fig. 2.

Of the parts of the engine, it is only desirable to note the cylinder casting 4, the intake manifold 5 and the exhaust manifold 6, which parts are of the standard or any suitable construction.

The carburetor proper is a self-contained structure and comprises the tubular mixing chamber 7 having a contracted portion adjacent its lower end, the float chamber -8, and air intake elbow 9. The mixing chamher 7 has a flanged upper end adapting it to be secured to the intake manifold 5 in the customary way, and it contains the customary throttle valve 10. The lower 23, 1919. Serial m 272,689.

\portion of the chamber 7 is provided with a) partition 11 which hasa depending nutequipped stem that supports an annular valve-seating plate 12. The'periphery of the plate 12 is spaced from the surrounding wall of the carburetor and normally supports an annular gravity-seated air intake valve 13. Spaced inward from the valve 13, the plate 12 has a raised hub 14 which serves to keep a constant air passage or clearance between the valve and hub, regardless of the distance that said valve may be raised in the air intake action. The stem depending from partition 11 is connected to the lower portion of chamber 7 by apartition 11 having spaced holes 11 therethrough forming air passages. The chamher 7 has a contraction at its lower end slightly above the partition 11. As the engine is in operation there may be some condensation of the liquid fuel on the walls of the intake passage. If so, this liquid would have a tendency to drip off the inner edge of said contraction into the ingoing air stream, so that it would be more readily picked up by the air stream than would be the case if the liquid adhered to the walls of the intake passage.

The improved carburetor has been especially designed for heating and vaporizing kerosene or hydro-carbons heavier than gasoline. The kerosene will be carried in a suitable tank and, in any of the well known means, will be delivered to the float 85 chamber 8 through a supply pipe 15 shown as coupled to a nipple 16 projected from one side of said chamber 8. The port in the tubular nipple 16 is adapted to be opened and closed to the desired extent by the cus- 90 tomary valve 17.

The level of the kerosene in the float chamber 8 is indicated by the dotted line .ez. The chamber 8 is provided at one side with a projected portion 8 that is 5 formed with a vertical passage 18, the lower portion of which is contracted at 18. A zigzag oil delivery conduit 19 connects the interior of the float chamber 8 to the passage 18. This conduit 19 is adapted to be opened 100 and closed to any desired extent by a suitable needle valve 19. The receiving end of said conduit 19 is below the liquid level 2-z but thedelivery end thereof into the passage 18 is above said liquid level. By reference to Fig. 2 it will be noted that the said delivery end of the conduit 19 is above the contracted lower extremity 18* of the passage 18, this being done for a purpose which will presently appear.

The upper extremity of the passage 18 is connnected to the receiving end of a pipe 20, as shown, by means of a coupling head 21 and cap screws 22. This pipe 20 has an intermediate portion that is subject to the heat from the exhaust manifold 6 of the engine, and preferably and, as shown, it is formed with a coiled portion 23 contained in the housing 24 that is bolted, or otherwise detachably secured directly on said exhaust manifold 6. The other end of said pipe 20 is connected to an elbow 25 that delivers into the mixing chamber 7 through a port 26 in one side of the latter, said elbow bein detachably secured to the body casting o the carburetor by cap screws 27.

l/Vorking within the float chamber 8 is a float 28 which operates the valve 17, in the usual way, to maintain a constant level of the kerosene in the said chamber. The operation of this improved carburetor is substantially as follows:

When partial vacuum or suction is produced in the main chamber 7 by the piston movement, the valve 13 will be raised to permit air to be drawn into said mixing chamher through the air intake elbow or member 9, and such partial vacuum or suction will also produce a partial vacuum in the preheating pipe 20. When a partial vacuum is produced in the said pipe 20, air will, of course, be drawn into the said pipe due to passage 18 and this contracted port 18*. In view of the contraction 18 a partial vacuum or suction will be produced in the kerosene delivery conduit 19 and kerosene will be drawn from the float chamber 8 and will be caused to overflow against the wall of the passage 18. The upwardly moving current of air in passage 18 and pipe 20 will carry the kerosene with it as fast as it is drawn from conduit 19. The fuel entering passage 18 through opening 19 is in part distributed on the walls of said passage. The vaporization of the fuel will be assisted by the heated walls on which it is thinly spread. The kerosene-laden air in preheated condition will be delivered into the mixing chamber 7 where it will be mixed with the additional or main supply of air which is drawn in through the elbow 9. Thus, good evaporization and thorough mixing of kerosene and air is accomplished before the explosive vapor is introduced into the intake manifold of the engine.

The contraction 18 at the lower end of the passage 18 insures a good current of air into tube 20 and affords a shoulder against which any surplus kerosene will lodge, and by which it will be delivered into direct contact with air that is drawn rapidly through the said contraction, and in this way, any kerosene not taken up by the upwardly moving air at an earlier time will be caught before it can drip down through the said contraction 18.

In this carburetor, the pipe 20. and passage 18 with the connections constitute what may be properly designated as a primary air intake passage, and the air passage through the elbow 9 may be treated as a valve-controlled auxiliary air intake passage.

This carburetor is especially designed for heating and vaporizing kerosene or hydrocarbons heavier than gasoline, and in such use, it will, of course, be understood that gasoline may be used to start the engine into action, this being a well known practice.

What I claim is:

1. A carburetor for internal combustion en ines provided with a mixing chamber, a

va ve-controlled air inlet at the bottom thereof, an air inlet conduit communicating with said chamber at an intermediate portion thereof, said conduit communicating with an air intake spaced from said mixing chamber and comprising a vertical cylindrical passage having a contracted lower end through which air enters, a liquid fuel supply chamber having a delivery conduit opening into said cylindrical passage through the vertical wall thereof and terminating flush with said wall at a point above the contracted lower end of said passage, and a throttle valve located adjacent the discharge end of said mixing chamber and serving to simultaneously control the suction through said valve controlled air inlet and through said second mentioned air inlet.

2. A carburetor for internal combustion engines provided with a mixing chamber, a float chamber, a valve controlled air inlet at the bottom of said mixing chamber, a constantly opened air inlet comprising a passage located at one side of said float chamber forming an air intake conduit and having a contracted opening at its lower end, a fuel intake passage opening into said passage and terminating flush with the wall thereof above the contracted opening and a conduit connected to said vertical passage and leading therefrom into the intermediate portion of said mixing chamber.

3. A carburetor for internal combustion engines provided with a mixing chamber, a throttle valve therein, a float chamber, a cylindrical passage at one side of said float chamber having an air intake conduit con-.

nected at its upper end, said passage having a contracted opening forming a shoulder at its lower end, a fuel intake passage having its receiving end below the level of the fuel at its other end with the mixing chamber bein the float chamber and its delivery end low the throttle valve. 10 above the level of the fuel and opening into In testimony whereof I afiix my signature the said passage and terminating flush with in presence of two witnesses.

the wall thereof above the contracted open- RAYMOND S. HILL.

ing therein, said vertical cylindrical passage being connected at its upper end to an exhaust heated tube, said tube communicating Witnesses: v

CLARA DEMAREST, Bnnmon G. BAUMANN. 

